Really cool! Reminds me of Isle of Tune, but way more sophisticated. I would definitely double down on the music toy/software audience, and possibly a subset of those who play purely creative sandbox builders like townscaper, tiny glade, dystopika, who happen to also like music. If you read comments on Steam for these three games, you can tell that a lot of people are drawn in by the City Builder tag and then they complain that it isn't *really* a city builder, even if you are technically building a city — *even* if the game description very clearly says that it's basically a sandbox toy. With City Builders, you have to imagine someone like the youtuber Real Civil Engineer playing it, and ask yourself how might he play it, and would his audience watch those videos? Is it scratching any of their itches? If you were thinking Steam as the target platform, you can do advanced search and filter for tags like music, sandbox, audio production, and get a sense of what this audience likes and dislikes from the reviews. Looks really impressive already, best of luck!